Description Cardisoma guanhumi, also known as the blue land crab, is a species of land crab found in tropical and subtopical estuaries and other maritime areas of land along the Atlantic coast of the Americas, from Brazil and Colombia, through the Caribbean, to the Bahamas, and as far north as Vero Beach, Florida. The species varies in colour from dark blue to brown or pale grey, and may grow to 11 centimetres (4.3 in) in width and weigh over 500 grams (18 oz)

The carapace of C. guanhumi can reach sizes up to around 11 cm (4.3 in) and overall reaching sizes of up to 35 cm (14 in). Males, like many crabs possess dimorphic claws: the larger claw can grow up to around 15 cm (5.9 in) in length, (eventually becoming larger than the carpace itself). The eyes are stalked and its colour ranges from a deep blue to a pale grey, juveniles generally have a brown carpace with orange coloured legs. Females usually appear light gray or white. Adult colours are usually present between 80 g (2.8 oz) and 180 g (6.3 oz). The species can weigh over 500 g (18 oz).